Collaboration services allow users of client machines to work together in creating and revising documents. For example, users may create documents on the users' own machines and then store the documents online (e.g., in the cloud), where others online can access the documents from any location to review the documents, provide comments, and make changes. Users may also create documents wholly online, e.g., using cloud-based application services, and may collaboratively edit the documents as described above.
Collaboration services are sometimes provided in connection with applications for web conferencing. As is known, web conferencing applications allow users of different client machines to engage in audio or video chats where participants can talk to one another and share data. In a typical arrangement, any participant has the option to share his or her desktop, or a portion thereof, with other participants, such that all participants can view the sharer's desktop on their own machines, along with any documents or applications displayed on the sharer's desktop. The sharer generally has control over the desktop and is able to open and edit documents while others observe. In some examples, the sharer can selectively grant control over the desktop to another participant, who can then operate the sharer's desktop via remote control. For example, a participant can send the sharer a request for desktop control and the sharer can grant the request. Using this interactive protocol, the sharer can pass control over the desktop to different participants one after another.